Alpha1-antitrypsin is the major alpha1-protein in normal human plasma and comprises about 90% of the anti-proteolytic activity in plasma. The purpose of this study is to determine the feasibility of preparing normal PiM alpha1-antitrypsin from the plasma of carefully screened donors who have been found to be free of testable liver abnormalitiese for supplementation in infants with alpha1-antitrypsin deficiency (PiZ) who have early symptoms of liver disease. Large-scale purification methods partially developed in this laboratory will be utilized for protein purification. Previoulsy initiated studies on the stability of the anti-proteolytic properties of this protein will be continued to determine the shelf-life of lyophilized protein stored at -20 degrees. Results to date indicate good stability up to greater than three years under some conditions studied.